Commuters began to feel the first major effects of overnight snowfall this morning – as forecasters’ predictions and a rare Met Office red alert for snow in Wales were proved vindicated.

Commuters, hospital and schools began to feel the first major effects of overnight snowfall this morning – as forecasters’ predictions and a rare Met Office red alert for snow in Wales were vindicated.

People woke up on Friday to thick snow and it wasn’t long before problems on the roads began with South Wales Police closing the M4 in both directions at Junction 36 at Bridgend due to the treacherous conditions.

There were said to be long tailbacks on the motorway stretch, including lorries unable to move because of becoming stuck in the snow.

Those travelling to work were being forced to make a variety of changes to their normal routine across Wales – including on the railway lines where there was major disruption early on.

An Arriva Trains Wales (ATW) spokesman said early services in Llandudno, between Lydney and Gloucester, Tondu, between Cardiff Central and Ninian Park on the city line and Cardiff Central and Ebbw Vale, had all been badly affected by the weather.

It had also caused signalling problems on the Rhymney Line at Ystrad Mynach.

An Arriva Trains Wales (ATW) spokesman said: “We have got disruption on multiple locations on the network as a result of heavy snowfall.

“We are still running services but there will be disruption because of the weather.

“We are trying to stick as closely to the timetable as possible but obviously this is being affected by the snow.

“We are advising passengers to visit www.journeycheck.co.uk/arrivatrainswales for the latest.”

Cardiff Bus urged people to check their website for the full list of affected services but high levels of internet traffic meant not everyone was able to access it.

The weather has also caused a headache for parents and students with hundreds of school closures set to force people into hasty arrangements for childcare and rearranged lectures.

There were in the region of between 80 and 90 full or partial school closures announced in Cardiff while Cardiff Metropolitan University closed all its campuses. Both campuses of University of Wales, Newport, were also shut - although efforts were being made for the City Campus to be opened for students wishing to access computer suites and the library.

Meanwhile, Cwm Taf Health Board has cancelled all outpatient appoints across its region for the whole of Friday.

There were also problems reported with electricity supplies in parts of South Wales with some power cuts in Ogmore, St Brides Major and Southerndown in the Vale of Glamorgan.

A forecaster for the Met Office said: “At the current time of 8am, we've had reports of about 20cm of snow lying at Senneybridge in Powys.

“Towards St Athan near Cardiff, we've got reports of about 2cm of snow. This is still being updated, so these areas and the rest of Wales can expect more snow across the day.

“We've got a red warning already in place in South Wales, where we'd expect 20 to 30cm of snow today. There are strong south easterly winds, particularly near the coast, which are liable to cause some blizzard conditions in places and perhaps some drifting.

“These are very challenging conditions which will remain for the rest of today. The band of rain, sleet and snow is going to become very slow moving as the day goes on, moving south eastwards.

“On the whole, it's going to be a very unpleasant day. I would advise people to keep abreast of forecast and if they live in the red warning zone, they should stick to essential journeys only.”

A spokesman for the Meteo Group, the weather forecasting arm of the Press Association, said: "There should be snow across Wales this morning, so everything is very much as predicted earlier in the week.

"It's set to carry on snowing through the day, but it should turn lighter as the day goes on.

"Over the next 24 hours, about 10 to 15 cm of snow can be expected across Wales, even as much as 20 to 25cm of snow over the mountainous areas in the south.

"We're expecting a frisk wind, which could cause blizzard conditions and low drifting in some places.

"Into the weekend, the snow should turn light and patchy. We're only expecting a few flurries on Saturday and Sunday. It will remain cold, but there shouldn't be any crazy weather past tomorrow."

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